1. Field of the Invention
The present invention relates generally to the field of food and beverage containers and to processes for manufacturing such containers. More specifically the present invention relates to a method of manufacturing a self-cooling container apparatus holding a carbonated beverage or other food item as described in U.S. Pat. No. 6,065,300 and to an improved container apparatus. The containers preferably contain a beverage, but other products are contemplated.
The apparatus includes an improved plastic receptacle which deforms laterally into a substantially cylindrical shape to fit into a plastic bottle or a metal container during manufacture. The receptacle is designed to be handled easily for manufacturing the self-cooling container, so that the processes that would be encountered during the manufacturing would be easily accomplished because of the way the receptacle is designed. The receptacle is further configured to match the shape of the bottom dome of a metal container to fully abut said bottom dome of the container so that during the beverage filling process, nitrogen or carbonation pressure transmitted from the beverage filler head to the inside space of the receptacle is fully transmitted to the bottom dome of the container and the pressure within the receptacle makes the receptacle rigid and stiff, and gives the container and receptacle combination the same column strength as pressurized container without a receptacle. The pressurization of the container with carbon-dioxide gas is important when carbonated beverage are being filled to ensure that the carbonation of the beverage occurs during the filling process. The beverage itself is usually uncarbonated until it enters the container, where, because of the absorption of pressurized carbon-dioxide gas, it becomes carbonated. For a container without the receptacle, the container column strength is obtained by the filler head firmly forming a seal with the empty open container rim and pressurizing the container directly with a blast of carbon-dioxide gas. The column strength of the container is obtained by the internal pressure of the container. This allows the filler head to firmly seal the rim of the container to maintain the pressure of the beverage during the filling process. However with the receptacle inside the container, the container no longer holds the carbonation pressure, and thus has very little column strength. By abutting the receptacle base directly, firmly and uniformly over the bottom inside base dome of the container and the bottom rim, the receptacle becomes rigid, strong and slightly taller than the container due to the pressure. Thus, during filling, the receptacle advantageously transmits the filler head forces directly to the container bottom dome wall without subjecting the container walls to deformation stresses. The slight elevation of the receptacle during the carbonated beverage filling process helps prevent direct contact of the weak unpressurized container walls with the filler head seal.
Other improvements to the apparatus include a refrigerant valve mounting structure centrally located on the receptacle bottom wall. The method of manufacture generally involves the broad steps of injection molding preforms from plastic material, blow molding the receptacle to a shape of particular form; cutting the top blow-domes of the manufactured receptacle with a laser or with a knife edge to obtain a uniform flange; orienting the receptacles for insertion into containers; inserting each receptacle into a container; filling the receptacle with beverage; seaming the container lid onto the receptacle and container flanges; checking for carbonation column strength of the filled and seamed container; and charging the annular space between the receptacle and container with refrigerant mixture; checking for refrigerant mixture leaks.
2. Description of the Prior Art
There have previously been self-cooling containers for food items including flexible and deformable beverage receptacles with widely spaced apart, rigid receptacle walls, and methods of manufacturing these containers. These prior art do not address the real issues of manufacturing and beverage plant operations that are crucial for the success of a self-cooling beverage container program. All prior art designs fail when subjected to the immense pressures (about 45 psi) of the carbonated filling process and fail to maintain the container column strength. The sudden blast of carbon-dioxide inside a container during filling, can destroy any thin-walled internal container, and collapse its walls so that the functionality of the apparatus will be impaired. Also, the sudden collapse of such internal containers, can cause the container itself to loose column strength, and collapse under the clamping force that is applied for sealing the container during filling. Many trials and designs were done to obtain the present configuration of the disclosed receptacle of this invention.
For example when an internal receptacle is used as a refrigerant storage receptacle, the beverage filler head pressurizes its external walls and crushes the receptacle, since such receptacles are generally made from thin walled materials for rapid heat transfer, they can be easily crushed by external pressure and cannot survive the forces of the high speed manufacturing process. Thus, failure of the internal receptacle, can also result in the sudden collapse of the container walls. Even with prior designs of co-seamed internal receptacles such as that described in U.S. Pat. No. 6,065,300 to the present inventor the problem was still not solved. Also, the high speed beverage plants require high speed compatible operations for manufacture of an online self-cooling beverage container. For example, prior art designs do not address easy valve insertion, self-aligning of the receptacle with the container and so on. Further, most prior art relies on a separate unintegrated manufacturing process for the attachment of the receptacle to the container.
Thus, a program to develop a self-cooling container that can address the rigors of the filling and the seaming stresses, as well as the tensions of processes such as beer pasteurization, must include the embodiments of the present improved invention. To operate the present invention for use as a self-cooling container, a valve is provided that is opened and a refrigerant mixture is progressively discharged from the receptacle, extracting heat from the container contents.
It is thus an object of the present invention to provide a self-cooling container and method of manufacturing a self-cooling container apparatus, the apparatus containing a beverage receptacle with a shape changing section, to either expand or contract the receptacle for easy insertion into the container.
It is another object of the present invention to provide a self-cooling container apparatus containing a beverage receptacle which is designed in a pre-expanded shape with a maximal volume, and with a pressure transfer bottom wall that transmits the carbonation beverage filling pressure directly to the container bottom wall to prevent the container side wall from collapsing.
It is an objective of the present invention to provide an apparatus and method of manufacture, that uses a receptacle that can contract to a smaller volume for easy insertion into the container, and then receptacle be re-expanded back to its original maximum volume state and that does not substantially expand after said re-expansion during the pressurized filling process to maintain stiffness and column strength.
It is another object of the present invention to provide such an apparatus in which a smaller volume of refrigerant mixture is exposed to a larger heat transfer surface area such as by corrugating the beverage receptacle wall, to increase the evaporation rate of the liquid refrigerant mixture.
It is an objective of the present invention to provide an apparatus and method of manufacture, that uses a beverage receptacle that can be seamed with the container and the lid so that a refrigerant mixture can be charged into the space between the container and the receptacle, causing the receptacle to contract to a smaller volume and allow the refrigerant to equilibrate in pressure with the internal receptacle pressure.
It is still another object of the present invention to provide such an apparatus which can be manufactured and assembled together in a simple series of steps.
It is an object of the present invention to provide such an apparatus which is inexpensive to manufacture, safe and reliable.
It is finally an object of the present invention to provide such an apparatus which can be flexible, and yet does not substantially change the head space of a beverage after filling and seaming.
The present invention accomplishes the above-stated objectives, as well as others, as may be determined by a fair reading and interpretation of the entire specification.
A self-cooling container apparatus for retaining a food item, including a container having a tubular container side wall and a container bottom wall having a certain configuration and being integrally joined to the container side wall and having a container lid; a receptacle having a tubular receptacle side wall and a receptacle bottom wall integrally joined to the receptacle side wall, the receptacle bottom wall having a configuration matching the certain configuration of the container bottom wall and abutting the container bottom wall such that pressure greater than ambient pressure within the receptacle is fully transmitted to the container bottom wall to enhance container column strength; the receptacle side wall and container side wall being spaced apart from each other to define therebetween a substantial annular space for retaining a two or three phase refrigerant mixture, the container side wall having a container side wall upper end configured as a container upper open rim with an outwardly angled container flange and the receptacle side wall having a receptacle side wall upper end configured as a receptacle flange which rests on the container flange and is sealed to the container flange upon affixing of the container lid over the receptacle flange and the container flange; and a food item release mechanism for releasing the food item from the receptacle and the container.
The container flange preferably is angled outwardly from the container upper open rim and the receptacle flange preferably is angled outwardly. The apparatus preferably additionally includes a refrigerant passing container port fitted with a refrigerant valve for receiving and releasing refrigerant. The refrigerant passing container port preferably is located in the container bottom wall. The configuration of the container bottom wall preferably includes an outwardly protruding annular container bottom wall rim on which the container rests; and the configuration of the receptacle bottom wall preferably an outwardly protruding annular receptacle bottom wall rim corresponding in size and shape to the container bottom wall rim so that the receptacle bottom wall rim nests within and abuts the container bottom wall rim and transmits pressure within the receptacle to the container bottom wall rim.
The refrigerant valve preferably is a check valve permitting refrigerant mixture to flow into the annular space between the receptacle side wall and the container side wall, and prevents the refrigerant mixture from escaping from the container unless released by manually operation of the refrigerant valve. The refrigerant valve receiving structure optionally includes an annular barrel protruding downwardly from the receptacle bottom wall; a check valve fitting closely within the annular barrel, the annular barrel being positioned to register with a downward deformation of the container bottom wall defining a hollow cylinder structure with a conical tip segment at the lower end of the hollow cylinder structure, the refrigerant passing container port being located at the lower end of the conical tip segment; and a sealing check valve within the hollow cylinder structure resting within and sealing the conical tip section against refrigerant mixture flowing out of the container through the refrigerant passing container port by virtue of the refrigerant mixture pressure of acting on said sealing check valve against ambient pressure, and which enters the annular barrel and moves away from the refrigerant passing container port when displaced mechanically by a refrigerant mixture charge valve stem 42 during refrigerant charging into the container, or by manually depressing an exposed portion of said check valve to cool the product. The refrigerant valve receiving structure preferably includes a tubular flange formed into the container bottom wall and opening at its lower end to define the refrigerant passing container port; and a self-contained check valve fitted sealingly within the tubular flange. The apparatus preferably additionally includes a refrigerant drainage channel depressed inwardly into the receptacle bottom wall and extending radially from the refrigerant valve to and out of the side of the receptacle; so that during charging, the refrigerant in liquid state charged into the container during refrigerant filling and remaining liquid after refrigerant filling and after temperature and pressure equilibration with the surrounding atmosphere after the apparatus is charged and stored and remaining at the bottom of the container between the container bottom wall and the receptacle bottom wall drains through the refrigerant drainage channel and along the annular space upon inversion of the container by a user to open the refrigerant valve to release the refrigerant to cool the food item, so that liquid refrigerant is not adjacent to the refrigerant valve and does not spray out of the container upon opening of the refrigerant valve.
A self-cooling container apparatus is further provided for retaining a food item, including a container having a tubular container side wall and a container bottom wall having a certain configuration and being integrally joined to the container side wall and having a container lid; a receptacle having a tubular receptacle side wall and a receptacle bottom wall integrally joined to the receptacle side wall; the receptacle side wall and container side wall being spaced apart from each other to define therebetween an annular space for retaining refrigerant, the receptacle tubular side wall including two axially separated half tube segments interconnected by integral axial and inwardly protruding side wall channels which define side wall bowing segments, the receptacle having a wider annular mid-section between the top and bottom of the receptacle, so that application of a certain inwardly directed force to the bowing segment ridges causes the ridges to become inverted to protrude into the receptacle and the depressed ridges to protrude more deeply inwardly and the remainder of the side wall bowing segments to draw closer together, reducing the receptacle cross-section sufficiently to fit into the container; and a food item release mechanism for releasing the food item from the receptacle and the container. The receptacle side wall preferably includes surface area increasing undulations for enhancing heat transfer through the receptacle side wall during refrigerant mixture release for more rapid and efficient cooling of the food item within the receptacle. The receptacle side wall preferably includes an outwardly protruding bulge stop, located close to the upper end of the receptacle side wall, which abuts the container flange after receptacle insertion into the container, through the container open upper rim for resisting movement of the receptacle out of the container.
A process of manufacturing the above-described self-cooling container apparatus for retaining a food item is provided, including the steps of orienting the receptacles for insertion into containers; inserting each receptacle into a container; filling each receptacle with beverage; filling the annular space between the container side wall and the receptacle side wall with refrigerant; seaming or crimping the container lid onto the container flange and the receptacle flange combined; and charging the annular space between the receptacle and container with refrigerant.
A process of manufacturing the self-cooling container apparatus for retaining a food item is further provided, including the steps of orienting the receptacles for insertion into containers; applying a certain inwardly directed force to the bowing segment ridges to cause the ridges to become inverted to protrude into the receptacle and the ridges to protrude more deeply inwardly and the remainder of the side wall bowing segments to draw closer together, reducing the cross-section of the receptacle sufficiently to fit into the container; inserting each the receptacle into a container; filling each receptacle with beverage; filling the annular space between the container side wall and the receptacle side wall with refrigerant; seaming the container lid onto the container; and charging the annular space between the receptacle and container with refrigerant. The certain inwardly directed force preferably is applied by creating at least a partial vacuum within each receptacle and mechanically pushing the receptacle bottom wall into the container. It is important that the maximum diameter of the receptacle be less that the diameter of the container side wall, so that the receptacle side wall never contacts the container side wall after insertion, since this could create radial and lateral stresses.
A process of manufacturing the self-cooling container apparatus for retaining a food item is further provided, including the steps of delivering a series of the receptacles to an orientation wheel on a receptacle conveyor mechanism; sequentially capturing the receptacles in the receptacle holding recesses along the circumference of the orientation wheel so that the receptacles are held loosely and co-axially as the orientation wheel rotates; placing below each receptacle an opening containing a substantially vertical spindle, so that the bottom wall of receptacles oriented upright rest on the spindles, and so that receptacles oriented up-side down receive the given the spindle below the given receptacle and slide onto the spindle and out of the orientation wheel; delivering the upright the receptacles remaining in the orientation wheel to a receptacle insertion station; inserting each receptacle into a container; filling each receptacle with beverage; filling the annular space between the container side wall and the receptacle side wall with refrigerant; seaming the container lid onto the container; and charging the annular space between the receptacle and container with refrigerant.
A receptacle orientation station is provided for orienting receptacles for insertion into containers to form self-cooling container structures for retaining food items, the orientation station including several receptacles, each having a tubular receptacle side wall and a receptacle bottom wall integrally joined to the receptacle side wall; a receptacle delivery mechanism for conveying a series of the receptacles; a receptacle wheel being rotatably and having a receptacle wheel rotation drive mechanism, the receptacle wheel having a receptacle wheel circumference with a series of spaced apart receptacle receiving recesses along the circumference the receptacle wheel, each recess for receiving and retaining a receptacle delivered to the receptacle wheel by the receptacle delivery mechanism, the recesses holding the receptacles substantially co-axially as the receptacle wheel rotates; several receptacle spindles, each receptacle spindle being located beneath each recess substantially along the axis of each receptacle in each recess; so that any of the receptacles oriented with the receptacle opening facing the spindle fall down around the spindle below the recesses, and so that any of the receptacles oriented with the receptacle opening facing away from their respective spindles rest on top of the spindles and continue to rotate with the receptacle wheel; and so that any of the receptacles remaining within the receptacle wheel simply rest on the orientation spindle as the receptacle wheel rotates for removal to another manufacturing station and any of the receptacles having exited their receptacles and resting around their respective spindles are removed for reorientation.
The spindles preferably retractably extend through ports in a orientation spindle wheel and the apparatus preferably further includes a spindle retraction mechanism which retract the spindles out of any of the receptacles resting over the spindles, so that the receptacles are freed from removal from the reorientation station. The orientation station preferably additionally includes an orientation cam in camming contact with the spindles for retracting the spindles into and extending the spindles out of the orientation spindle wheel such that the spindles fall below the flanges of receptacles resting over the spindles so that any of the receptacles dropping over the spindles are delivered by rotation of the orientation spindle wheel to a recycling station where the receptacles are again delivered by to the orientation station.